Errors

Error response shape

Non-2xx responses return JSON:

{
  "error": "machine_readable_code",
  "message": "Human-readable description.",
  "requestId": "req_abc123..."
}

Code	When
`200 OK`	Successful read
`201 Created`	Resource created
`202 Accepted`	Async operation queued (e.g. build dispatch)
`204 No Content`	Successful write with no body
`400 Bad Request`	Invalid input
`401 Unauthorized`	Missing or invalid token
`403 Forbidden`	Token lacks permission for this action
`404 Not Found`	Resource doesn’t exist or you can’t see it
`429 Too Many Requests`	Rate-limited; see `Retry-After` header
`500 Internal Server Error`	Bug on our side — include `requestId` when reporting

Code	Description
`invalid_token`	Token is malformed, revoked, or expired.
`insufficient_scope`	Token doesn’t have the required permission.
`validation_failed`	Input failed schema validation.
`engine_not_found`	Requested `ueVersion` is not supported.
`repo_not_accessible`	GitHub App lost access to the repo.
`perforce_auth_failed`	Perforce credentials rejected.

When rate-limited:

HTTP/1.1 429 Too Many Requests
Retry-After: 12

Wait Retry-After seconds before the next request.